Here are my suggestions.
Go to
Free Sex Movies Free Porn Video Clips - 89.com . They have lots of different categories and each category features a short clip. The clips change daily, and they tell you what movie the clip is from. If you find a clip that you and your wife like and want to see more of, write down the name of the movie and then see if you can find it.
Another suggestion is to make a free account on
www.myfreepaysite.com . It really is free, you just have to give them your e-mail address and then they send you a password so that you can login. Once you are logged in, click on Flash Video Theater... it will take you to an area where you can watch full movies.
Enjoy!